The Upper Palaeozoic Fossils of Missouri. — Rozvley. 345 . 
tiires to slits ; anal opening- surrounded by an elevated rim and 
often strong hood-like upper prolongation of the anal deltoid 
or interradius ; ornamentation, fine lines, coarse cord-like folds, 
or crenulated lines; columnar cicatrix rather large, but the col- 
umn is unknown, so also tlie pinnies. The central opening 
above (ventral) confined to a lunular area and, in perfect speci- 
mens, covered by an integument of small plates. 
The genus begins in the Kinderhook or the so-called Lower 
Chouteau beds and extends through the Lower Burlington. 
Lophoblastus conoideus, n. sp. 
Plate xxviii. 
Fig. I. — Side view, two diameters, of a large specimen. 
Fig. 2. — Ventral view, two diameters, of another specimen. 
Fig. 3. — Side view of a large elliptical specimen, natural si^c. 
Fig. 4. — Side view of a specimen, probably of a different species. 
Body small, conoidal or elliptical. Base large, convex and com- 
posed of the usual three plates. Columnar scar medium in size and 
excavated. Interradials from one-fourth to one-fifth the length of the 
body. Radials more than half the length of the body. The lower ends 
of the ambulacra project outward. The spiracles are round or slightly 
elongate openings and the anal opening is rather large and with a less 
pronounced hood than any of the other species, excepting Loplwblastiis 
roemeri. The ornamentation is fine or coarse lines parallel with the 
plate sutures. The elongate triangular areas bounding the ambulacra 
as marginal parts of the radials are less pronounced than in the type 
species. 
The specimens of this species were collected from Lpper 
Chouteau beds, two and one-half miles northeast of Curry- 
ville, Mo. 
This fossil was figured along" with GraJiatocriiiiis inntabilis 
under the impression that it belonged to the same species, but 
better specimens lately obtained show the greatest difference 
between them. 
Lophoblastus marginulus, n. sp. 
Pl.\te xxvin. 
Fig. 18. — Ventral view of a specimen with the central opening 
covered by an arch of minute plates extending a little way 
over the ambulacra. 
Fig. 19. — Side view of the body of the type specimen, showing 
the character of ornamentation and the little rim around the 
stem base. 
The collection contains four of these little blastoids. The base is 
flat or a very little convex. The lower ends of the ambulacra are 
